Comparison of fluorescence in-situ hybridisation with dual-colour in-situ hybridisation for assessment of HER2 gene amplification of breast cancer in Hong Kong

• Published in: Hong Kong medical journal = Xianggang yi xue za zhi 2016-04, Vol.22 (2), p.144-151
• Main Authors: Tang, Scott M C, Soong, Inda S, Luk, M Y, Suen, Dacita T K, Hioe, F, Man, Ellen P S, Tsun, Obe K L, Khoo, U S
• Format: Article
• Language: English
• Subjects: Breast Neoplasms - genetics; Breast Neoplasms - pathology; Female; Gene Amplification; Hong Kong; Humans; Immunohistochemistry; In Situ Hybridization - methods; In Situ Hybridization, Fluorescence - methods; Neoplasm Invasiveness; Receptor, ErbB-2 - genetics; Reproducibility of Results; Retrospective Studies
• ISSN: 1024-2708
• DOI: 10.12809/hkmj144458

To compare the PathVysion fluorescence in-situ hybridisation assay with the INFORM HER2 Dual in-situ hybridisation assay on 104 invasive breast cancers with a broad spectrum of immunohistochemistry scores. This case series involved consecutive patients diagnosed with invasive breast carcinoma with equivocal immunohistochemistry score and referred for further HER2 assessment from the departments of Surgery and/or Clinical Oncology of the two hospitals between January 2013 and February 2014. An additional 10 cases with negative HER2 immunohistochemistry and 11 cases with positive HER2 immunohistochemistry were further included. The results of both fluorescence in-situ hybridisation and dual in-situ hybridisation were available in 99 of 104 cases, respectively. Student’st test showed no statistically significant difference in the mean number of HER2 count, CEP17 copies, or HER2/CEP17 ratio between that obtained by fluorescence in-situ hybridisation and that obtained by dual in-situ hybridisation. Pearson’s correlation of results for the two assays was strong for HER2/CEP17 signal ratio (R=0.963, P